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631.
Water Footprint of the Palestinians in the West Bank1 总被引:1,自引:0,他引:1
Dima W. Nazer Maarten A. Siebel Pieter Van der Zaag Ziad Mimi Huub J. Gijzen 《Journal of the American Water Resources Association》2008,44(2):449-458
Abstract: Water in the West Bank of Palestine is a key issue due to its limited availability. Water is used from own sources for domestic, industrial, and agricultural purposes. Moreover, water is consumed in its virtual form through consumption of imported goods, such as crops and livestock, the production of which used water in the country of production. In addition, wastewater in many parts of the West Bank is disposed off without treatment into the wadis, deteriorating the quality of the water resources in the area and, therefore, further reducing the quantity of good quality water available. This paper calculates the water footprint for the West Bank. The consumption component of the water footprint of the West Bank was found to be 2,791 million m3/year. Approximately 52% of this is virtual water consumed through imported goods. The West Bank per capita consumption component of the water footprint was found to be 1,116 m3/cap/year, while the global average is 1,243 m3/cap/year. Out of this number 50 m3/cap/year was withdrawn from water resources available in the area. Only 16 m3/cap/year (1.4%) was used for domestic purposes. This number is extremely low and only 28% of the global average and 21% of the Israeli domestic water use. The contamination component of the water footprint was not quantified but was believed to be many times larger than the consumption component. According to the official definition of water scarcity, the West Bank is suffering from a severe water scarcity. Therefore, there is a need for a completely new approach towards water management in the West Bank, whereby return flows are viewed as a resource and that is geared towards a conservation oriented approach of “use, treat, and reuse.” 相似文献
632.
The aim of this study is to explain the occurrence of food sharing across primates. Defined as the unresisted transfer of food, evolutionary hypotheses have to explain why possessors should relinquish food rather than keep it. While sharing with offspring can be explained by kin selection, explanations for sharing among unrelated adults are more controversial. Here we test the hypothesis that sharing occurs with social partners that have leverage over food possessors due to the opportunity for partner choice in other contexts. Thus, we predict that possessors should relinquish food to potential mates or allies, who could provide or withhold matings or coalitionary support in the future. We used phylogenetic analyses based on both maximum likelihood and Bayesian approaches in a sample of 68 primate species to test these predictions. The analyses strongly indicate that (1) sharing with offspring is predicted by the relative processing difficulty of the diet, as measured by the degree of extractive foraging, but not overall diet quality, (2) food sharing among adults only evolved in species already sharing with offspring, regardless of diet, and (3) male–female sharing co-evolved with the opportunity for female mate choice and sharing within the sexes with coalition formation. These results provide comparative support for the hypothesis that sharing is “traded” for matings and coalitionary support in the sense that these services are statistically associated and can thus be selected for. Based on this, we predict that sharing should occur in any species with opportunities for partner choice. 相似文献
633.
Carmen Lidia Chiţescu Anca Ioana Nicolau Paul Römkens H. J. Van Der Fels-Klerx 《Journal of environmental science and health. Part. B》2013,48(7):457-467
Use of pharmaceuticals in animal production may cause an indirect route of contamination of food products of animal origin. This study aimed to assess, through mathematical modelling, the transfer of pharmaceuticals from contaminated soil, through plant uptake, into the dairy food production chain. The scenarios, model parameters, and values refer to contaminants in emission slurry production, storage time, immission into soil, plant uptake, bioaccumulation in the animal's body, and transfer to meat and milk. Modelling results confirm the possibility of contamination of dairy cow's meat and milk due the ingestion of contaminated feed by the cattle. The estimated concentration of pharmaceutical residues obtained for meat ranged from 0 to 6 ng kg?1 for oxytetracycline, from 0.011 to 0.181 μg kg?1 for sulfamethoxazole, and from 4.70 to 11.86 μg kg?1 for ketoconazole. The estimated concentrations for milk were: zero for oxytetracycline, lower than 40 ng L?1 for sulfamethoxazole, and from 0.98 to 2.48 μg L?1 for ketoconazole. Results obtained for the three selected pharmaceuticals indicate a minor risk for human health. This study showed that supply chain modelling could be an effective tool in assessing the indirect contamination of feedstuff and animal products by residues of pharmaceuticals. The model can easily be adjusted to other contaminants and supply chain and, in this way, present a valuable tool to underpin decision making. 相似文献
634.
Biodiversity Conservation in Local Planning 总被引:1,自引:0,他引:1
JAMES R. MILLER†† MARTHA GROOM† GEORGE R. HESS‡ TODDI STEELMAN‡ DAVID L. STOKES† JAN THOMPSON§ TROY BOWMAN§ LAURA FRICKE BRANDON KING‡ RYAN MARQUARDT§ 《Conservation biology》2009,23(1):53-63
Abstract: Local land-use policy is increasingly being recognized as fundamental to biodiversity conservation in the United States. Many planners and conservation scientists have called for broader use of planning and regulatory tools to support the conservation of biodiversity at local scales. Yet little is known about the pervasiveness of these practices. We conducted an on-line survey of county, municipal, and tribal planning directors (n = 116 ) in 3 geographic regions of the United States: metropolitan Seattle, Washington; metropolitan Des Moines, Iowa; and the Research Triangle, North Carolina. Our objectives were to gauge the extent to which local planning departments address biodiversity conservation and to identify factors that facilitate or hinder conservation actions in local planning. We found that biodiversity conservation was seldom a major consideration in these departments. Staff time was mainly devoted to development mandates and little time was spent on biodiversity conservation. Regulations requiring conservation actions that might benefit biodiversity were uncommon, with the exception of rules governing water quality in all 3 regions and the protection of threatened and endangered species in the Seattle region. Planning tools that could enhance habitat conservation were used infrequently. Collaboration across jurisdictions was widespread, but rarely focused on conservation. Departments with a conservation specialist on staff tended to be associated with higher levels of conservation actions. Jurisdictions in the Seattle region also reported higher levels of conservation action, largely driven by state and federal mandates. Increased funding was most frequently cited as a factor that would facilitate greater consideration of biodiversity in local planning. There are numerous opportunities for conservation biologists to play a role in improving conservation planning at local scales. 相似文献
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638.
J. Van Keirsbilck M. Cannie C. Robrechts T. de Ravel S. Dymarkowski T. Van den Bosch D. Van Schoubroeck 《黑龙江环境通报》2006,26(8):684-688
We present a case of sirenomelia diagnosed on a first trimester ultrasound at 10 weeks' gestation and confirmed on 3D-ultrasound and MRI. The pregnancy was terminated at 15 gestational weeks and the post-mortem examination, including RX and microscopy, is presented. The sirenomelia sequence is a rare and lethal anomaly characterized by fusion, rotation, hypotrophy or atrophy of the lower limbs and severe urogenital abnormalities leading to oligohydramnios in the second half of pregnancy. Our case illustrates that the diagnosis of sirenomelia can be reliably made in the first trimester. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
639.
S. Claassens L. Van Rensburg K. J. Riedel J. J. Bezuidenhout P. J. Jansen Van Rensburg 《The Environmentalist》2006,26(1):51-62
Summary Bioremediation has become an important method for the treatment of terrestrial oil spills and is often favoured over strictly
physical-chemical methods. In this study, enzymatic analyses and signature lipid biomarkers were employed to evaluate the
efficacy of selected bioremediation products on control and oil contaminated soil plots. It is envisioned that these biological
indicators may be used as possible adjuncts to the strictly physical-chemical criteria most commonly employed. The application
of the enzymatic and signature biomarker methods for product evaluation proved successful. The enzymatic assays provided a
valuable insight into shifts in the functional diversity of the soil microbial communities resultant from the various treatments.
Stimulation or inhibition of the microbial communities as a result of the various treatments was also demonstrated, particularly
with regards to dehydrogenase activity. Phospholipid fatty acid profiles proved sufficiently sensitive to allow differentiation
between products and resultant microbial communities that corresponded to satisfactory and unsatisfactory petroleum hydrocarbon
removal. 相似文献
640.